The Simpson Deck-Drive DCU Composite Screw in #10 x 2-3/4", finished in Type 316 Stainless Steel with a Red painted cap head, is purpose-built for fastening composite and PVC decking in demanding outdoor environments. Engineered by Simpson for severe-level corrosion resistance, this deck screw is especially suited for installations near saltwater, pools, or other chloride-rich settings where standard fasteners fail prematurely. The color-matching red painted head blends with popular composite decking brands, delivering a clean, professional appearance that conceals the fastener for a finished look installers and homeowners expect.

Key Features

• Type 316 Stainless Steel finish - provides severe-level corrosion resistance, standing up to chlorides, saltwater exposure, and harsh coastal or poolside environments where lesser alloys corrode quickly.
• Type-17 Point - penetrates composite and PVC decking cleanly without pre-drilling, saving installation time and reducing board splitting risk.
• Inverted upper Tri-Lobe threads - clear excess material as the screw drives, preventing mushrooming at the surface and ensuring a flush, secure installation every time.
• Cap Head design with 0.230 in. head diameter - sits flush against the decking surface for a low-profile, snag-free finish that looks intentional rather than industrial.
• T20 6-Lobe drive type - provides positive bit engagement, reducing cam-out during driving and keeping the installation fast and frustration-free.
• Red color-matching painted head - blends with popular composite decking manufacturers' colors so fasteners disappear into the deck surface for a more concealed, polished result.
• 2-3/4 in. length - sized to achieve proper penetration depth through composite decking boards into the framing below for a strong, lasting hold.

Why This Product

• Composite and PVC decking requires a screw designed specifically for the material - the DCU's Type-17 point and Tri-Lobe threads are engineered to penetrate without cracking boards or leaving raised material around the head, problems common when standard wood screws are used on composite.
• For decks near the ocean, on docks, or around pools, standard stainless steel is often not enough - Type 316 Stainless Steel is selected specifically for its resistance to chloride-driven corrosion, making this screw the right choice for severe coastal and poolside applications.
• The red painted cap head is designed to match popular composite decking colors, eliminating the visible contrast of a bare metal fastener head and giving the finished deck a more professional, intentional appearance.
• The T20 6-Lobe drive system reduces bit slippage during installation, which means fewer stripped heads, less wasted material, and a cleaner result across an entire deck project.

Specifications

• Brand: Simpson Strong-Tie
• Screw Size: #10
• Length: 2-3/4 in.
• Head Diameter: 0.230 in.
• Head Type: Cap Head
• Drive Type: T20 6-Lobe
• Thread Type: Tri-Lobe Threads
• Point Type: Type-17 Point
• Material: Type 316 Stainless Steel
• Finish: Type 316 Stainless Steel
• Color: Red

Available Pack Options

• DCU234C316RD: 70 Pk - includes 1 driver bit included
• DCU234P316RD: 350 Pk - includes 1 driver bit included
• DCU234MB316RD: 1750 Pk - includes 2 driver bits included

Approved Applications

• Composite decking fastening - all types of composite decking boards
• PVC decking installation
• Coastal and marine-adjacent deck projects where chloride exposure is a concern
• Pool deck installations and other high-moisture, high-chloride outdoor environments

Frequently Asked Questions

Why is Type 316 Stainless Steel specified for this screw instead of standard stainless?

Type 316 Stainless Steel is chosen specifically because it provides severe-level corrosion resistance, particularly against chlorides. This makes it well-suited for applications near saltwater, swimming pools, or other environments where chloride exposure would cause standard fasteners to corrode and fail over time.

Do these screws require pre-drilling into composite or PVC decking?

No. The Type-17 Point is designed to penetrate composite and PVC decking directly without the need for pre-drilling, simplifying installation and reducing the number of steps required to complete the job.

What drive bit is recommended for the DCU Composite Screw?

The DCU Composite Screw uses a T20 6-Lobe drive. The compatible replacement driver bit is listed in the Related Products section below. Using the correct bit ensures positive engagement and minimizes cam-out during driving.

How do the inverted upper Tri-Lobe threads improve installation quality?

The inverted upper threads are engineered to clear excess composite material as the screw is driven into the board. This prevents the material from mushrooming or bulging around the screw head, resulting in a clean, flush surface without the need for additional finishing steps.

Downloads and Resources

• Composite-Decking Color Cross-Reference chart

Related Products

• BIT20T-2-R2 - Compatible T20 6-Lobe driver bit for use with the DCU Composite Screw
• Deck-Drive Screw Plug Solution - Color-matching DCU Screw Plugs compatible with the DCU Composite Screw